Suppressing role of miR-520a-3p in breast cancer through CCND1 and CD44.

Recent studies show that many microRNAs (miRNAs) are found to play important roles in breast cancer, however, most of miRNAs are not investigated completely. In the present study, significant down-regulation of miR-520a-3p was found in the breast cancer tissues and cell lines. The restoration of miR-520a-3p expression in breast cancer cells could inhibit cell proliferation, migration and invasion. In addition, miR-520a-3p was able to induce breast cancer cell apoptosis. Luciferase assay was used to confirm that CCND1 and CD44 were the direct target genes of miR-520a-3p. The ectopic expression of miR-520a-3p repressed CCND1 and CD44 expression on post-transcriptional levels in breast cancer cells. This study suggests that miR-520a-3p may act as an optional method for breast cancer therapy.